Turkana tribesmen walk with guns in order to protect their cattle from rival Pokot and Sambur tribesmen near Baragoy, Kenya February 14, 2017. Cattle rustling and competition for grazing have long troubled northern Kenya, but severe drought and political rivalries ahead of the elections have exacerbated the situation between ethnic tribes. (Photo by Goran Tomasevic/Reuters)

A hippopotamus is sprayed with water on a hot summer day at Anna National Zoological Park in Chennai, India on April 26, 2017. (Photo by Arun Sankar/AFP Photo)

Mongolian President Tsakhiagiin Elbegdorj (C) walks towards the media after casting his vote for the parliamentary elections at a polling station in Ulaanbaatar, Mongolia, June 29, 2016. (Photo by Jason Lee/Reuters)

A view of the construction site of the Chateau de Guedelon near Treigny in the Burgundy region of France, September 13, 2016. Blacksmiths, stonemasons and quarry men are hard at work in a Burgundy forest building a 13th-century-style castle using the most basic tools and materials, replicating the methods used hundreds of years ago to better understand them. (Photo by Jacky Naegelen/Reuters)

In this October 6, 1976 file photo a member of a Thai political faction strikes at the lifeless body of a hanged student outside Thammasat University in Bangkok October 6, 1976. For some Thais, the bloody events of October 6, 1976 are still a nightmare. On that day, heavily armed security forces shot up Bangkok's Thammasat University campus and killed scores of students, while right-wing vigilantes captured would-be escapees, subjecting them to ghoulish lynchings. (Photo by Neal Ulevich/AP Photo)

A North Korean war veteran is decorated with medals as he attends a parade to celebrate the anniversary of the Korean War armistice agreement, Sunday, July 27, 2014 in Pyongyang, North Korea. North Koreans gathered at Kim Il Sung Square as part of celebrations for the 61st anniversary of the armistice that ended the Korean War. (Photo by Wong Maye-E/AP Photo)

The book “Elektroschutz in 132 Bildern” (Electrical Protection in 132 Pictures) was published in Vienna in the early 1900s by a Viennese physician named Stefan Jellinek (1878-1968, a founder of the Electro-Pathological Museum). The pictures are nice and direct and unambiguous; they teach, graphically, that the surest way to kill yourself with electricity is to form a complete path from source (usually the bright red arrow) to ground (the screened back, pink arrow). Arrowheads provide the path for current flow. (Photo by The Vienna Technical Museum)

A student of the Orchestra of Recycled Instruments of Cateura holds an instrument made from recycled material by craftsman Nicolas Gomez, in Cateura, near Asuncion, May 9, 2013. The orchestra is the brainchild of its conductor Favio Chavez, who wanted to help the children of garbage pickers at the local landfill, and the instruments are made from salvaged materials by craftsman Gomez. The orchestra now involves 30 schoolchildren who have toured countries in Latin America, North America and Europe to play music ranging from Beethoven and Mozart to the Beatles and Paraguayan folk songs. (Photo by Jorge Adorno/Reuters)